Fixator for diaphyses fractures

ABSTRACT

A fixator for diaphyses fractures comprising two fixation nails held between two parallel connection members. Each connection member possesses two parts detachably connected with one another through the agency of at least one spring or resilient element. At the corresponding parts of both connection members there are adjustably and detachably secured, on the one hand, one of the fixing nails and, on the other hand, a support disposed in a plane which is substantially perpendicular to a plane taken through the fixation nails, such support having a respective pair of crosswise arranged fixing wires.

United States Patent 91 Riniker [451 Apr. 17, 1973 [5 FIXATOR FOR DIAPHYSES 2,406,987 9/1946 Anderson ..128/92 A FRACTURES 2,687,720 8/1954 Haboush ...128/84 R 1,997,466 4/1935 Longfellow 128/84 R [76] Inventor: Paolo Riniker, Via Valle Maggia, I

110631110, Switzerland Primary Examiner-Richard A. Gaudet [22] Filed: 17, 1972 Assistant Examiner-J. Yasko Appl. No.: 227,132

Foreign Application Priority Data Mar. 16, 1971 Switzerland ..3814/71 US. Cl. ..l28/92 A, 128/84 R Int. Cl. ..A61f 5/04 Field of Search ..l28/92 R, 92 A, 92 B,

128/92 E, 84 R, 84 B, 84 C, 83, 87

References Cited UNITED sTATEs PATENTS 2/1950 Persall .128/92 A 8/1932 Youngren Attorney-Werner W. Kleeman ABSTRACT A fixator for diaphyses fractures comprising two fixation nails held between two parallel connection members. Each connection member possesses two parts detachably connected with one another through the agency of at least one spring or resilient element. At the corresponding parts of both connection members there are adjustably and detachably secured, on the one hand, one of the fixing nails and, on the other hand, a support disposed in a plane which is substantially perpendicular to a plane taken through the fixation nails, such support having a respective pair of crosswise arranged fixing wires 5 Claims, 3 Drawing Figures wwiwmsa EMEEEEEE FIXATOR FOR DIAPHYSES FRACTURES BACKGROUND OF THE INVENTION The present invention relates to a new and improved fixation device, conveniently referred to herein as fixator, for diaphyses fractures and is of a type incorporating' two fixing nails held between two parallel connection members or supports.

The use of the heretofore known fixators of the aforementioned type has associated therewith a series of disadvantages. On the one hand, there exists the danger that owing to decomposition of the bone, which occurs at the fracture joint, there arises a dehiscence between the fragments, promoting the formation of pseudoarthrosis. Furthermore, the bone tends to become more porous at the region of the fracture owing to the absence of any load.

SUMMARY OF THE INVENTION Hence, from what has been explained above it should be apparent that the medical art is still in need of a fixator for diaphyses fractures which is not associated with the aforementioned drawbacks and limitations of the prior art constructions. Thus, it is a primary objective of the present invention to provide a fixator for diaphyses fractures which effectively and reliably fulfills the existing need in the art and is not associated with the aforementioned drawbacks and limitations of the prior art constructions.

Another and more specific object of the present invention relates to a new and improved construction of fixator for diaphyses fractures which not only overcomes the aforementioned drawbacks of the prior art constructions but is relatively economical to manufacture and easy to use.

Now, in order to implement these and still further objects of the invention, which will become more readi- Iy apparent as the description proceeds, the fixator of this invention is generally manifested by the features that each connection member possesses two parts such support having a pair of crosswise arranged fixing wires.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood and objects other than those set forth above,will become apparent when consideration is given to the following detailed description thereof. S uch description makes reference to the annexed drawings wherein:

FIG. 1 is a perspective view of a preferred constructional form ofinventive fixator for diaphyses fractures;

FIG. 2 is a schematic longitudinal sectional view V through a fractured hollow bone and one of the conmotion or bracing members; and

FIG. 3 is a sectional view taken substantially along the line III-III of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Describing now the drawings the illustrated exemplary embodiment of fixator for diaphyses fractures possesses two parallel, bipartitie connection members 1 and 2. One part of each such two-piece connection member 1 and 2 is in the form of a hollow rod 3 and the other part is constructed as a sleeve or sleeve member4 which is slipped or displaced over such hollow rod 3. In this regard the dimensions are chosen such that the inner hollow rods 3 protrude at both ends 5 and 6 past the associated sleeve members 4. Now upon the threaded protruding ends 5 and 6 of each of the hollow rods 3 there are threadably connected two respective adjusting nut members 7 and 8 while interposing respective spring or resilient elements 9 and 10. On the one hand these spring elements 9 and 10 bear against the associated edge of the corresponding sleeve member 4 and on the other hand against the associated adjusting nut member 7 and 8 confronting the relevant end face of such sleeve edge. In the illustrated embodiment the resilient or spring elements 9 and 10 are each composed of a multiplicity of stacked spring discs 11 which are pushed onto the associated inner hollow rod 3. By tightening the adjusting nut members 7 and 8 it is possible to resiliently connect each hollow rod 3 with its associated sleeve member 4, the intimacy of such connection being dependent upon the spring pressure and thus also being adjustable, whether such be by virtue of the degree of tightening of the adjustment nut members 7 and 8 or by virtue of the number of resilient discs 11 which are used.

At the upper end of each hollow rod 3 there is fixedly connected therewith a clamping mechanism 12 for a fixation nail 13, whereas a corresponding clamping mechanism 14 is secured to the lower end of each sleeve member 4 for a fixation nail 15. These clamping mechanisms 12 and 14 are positionally secured in axial direction by means of the adjustment nut members 16 and 17, respectively, so that following loosening of such adjustment nut members they can be displaced along the hollow rods 3 and along the sleeves 4. This provides the possibility of changing the spacing of both fixation or fixing nails 13 and 15. 7

Continuing, at both connection members 1 and 2 there are further displaceably retained by means of the adjusting nut members 20 and 21 two half moonshaped supports or carriers 18 and 19, each of which is located in a plane perpendicular to an imaginary plane taken through the fixing nails 13 and 15. One of these supports, such as the support 18, is connected with the hollow rods 3 and the other support, in this case the support 19, with the sleeve members 4. Each of these support 18 and 19 consists of two hingedly interconnected support wings or blades 18a and 18b and 19a and 19b respectively. Further, each support 18 and 19 possesses four connection slots or grooves 22 for a respective tightening or clamping screw 23 serving to hold two respective crosswise arranged fixing or fixation wires 24. By appropriately displacing the clamping screws 23 it is possible within certain limits to change the position of such wires 24 at each support 18 and 19 respectively.

During use of the fixator under discussion the fixing nails 13 and are driven through the bone 25 at a respective end of such broken bone, that is to say at the region of the joint, whereas the fixing wires 24 pass directly through both sides of the fracture location 26 of the bone after the position of the fixing nails 13 and 15 not only has been accommodated to the connection members 1 and 2 but also after the fixing wires 24 have been accommodated to the dimensions of the broken bone 25 as well as the position of the fracture location 26 for each individual case encountered.

Now the described fixator apparatus is capable of avoiding the previously mentioned drawbacks of the heretofore known state-of-the-art fixators in that the fracture location can be loaded to an adjustable degree. Such loading of the fracture location then arises when the displacement force produced by the weight load between the hollow rods 3 on the one hand and the sleeve members 4 on the other hand is greater than the spring force exerted by the spring or resilient elements 9 and 10. In such case the weight of the patient is partially transmitted from the fixing nail 13 via the hollow rods 3, the support 18 and its fixing wires 24 to the proximal fracture piece 27 and therefore to the fracture location 26, whereas the distal fracture piece 28 is supported against the fixing nail 15' through the agency of the fixing wires 24 associated with the support 19 and the sleeve members 4. Such partial loading of the fracture location 26 as well as the degree of such loading is now dependent upon the connection force exerted by the spring elements between both parts 3 and 4 of the connection members 1 and 2. As already previously explained this force can be adjusted in two ways, namely on the one hand by the number of intermediately disposed resilient or spring discs 11, and on the other hand especially by the pressure exerted by the adjustment screws 7 and 8.

By virtue of such loading of the fracture location which,'if desired, can be increased during the course of the healing process, there is eliminated both the risk of formation ofa pseudoarthrosis as well as bone porosity,

since such loading of the fracture location during movement is intermittent, so that by virtue of the thus 1 brought about pulsations at'thebone there is alternately produced a pressure and suction effect at the blood vessels.

If there is present, for instance, a fragmentation or defect fracture then both of the fragments 27 and 28 near the joint must be completely rigidly fixed in their anatomically correct position, that is to say, by tightening the nut members 7 and 8 the resilient or spring elements 9 and 10 must be pre-stressed so intensely that a force-locking connection prevails between the hollow rods 3 on the one hand and the sleeve members 4 on the other hand. If, after a certain time, callous tissue has formed between the broken fragments then, for instance, the nut members 7 can be loosened somewhat and thus there is brought about a less intensive loading pressure. With progressive consolidation of the fracture this axial load can be increased by further loosening the relevant nut members.

The described fixator, on the one hand, prevents movement between the fragments and, on the other hand, however permits an axial loading, so that already at a very early point in time, by virtue of such loading,

the newly formed structure can adjust itself to the static load.

Furthermore, the contact pressure between both fragments is elastic since the fixing wires 24 as such always have associated therewith a certain elasticity which, moreover, can be likewise accommodated to the requirements of the individual case encountered by suitable selection of the diameter and the material of such wires. Owing to the arrangement of crossed and as such resilient fixing wires 24 there is attained the required positional stability of the fractured pieces, by

means of which the intermittent loading of such frac-- tured pieces can be undertaken without risk. Additionally, this stability of the relative position of the fractured pieces is also then ensured even if the diameter of the bores for the fixing nails 13 and 15, increases with time, for instance owing to inflammation.

The described fixator additionally is suitable not only for the extension but also for the reposition of the fracture in that it is readily possible, by means of the adjustment or positioning nut members 16 and 17, to move the fixing nail 13 relative to the fixing nail is away from one another in the sense of separating the fragments, to the extent such is required in the individual case, to bring both fragments into the correct position, and thereafter in the oppositemanner to undertake the reposition work. Hence extension and reposition can be undertaken with the same fixator, whereas previously two different devices had to be used.

Finally, the half moon-shape of the supports 18 and 19 for instance enables carrying out operative incisions or performing surgical operations by readily removing or displacing away such supports, whereby removal thereof is facilitated in that the supports consist of two wings or blades which can be pivoted towards one another.

While there is shown and described present preferred embodiments of the invention, it is to be distinctly understood that'the invention is not limited thereto but may be otherwise variously embodiedand 1 practice within the scope of the following claims,

What is claimed is:

l. A fixator for diaphyses fractures, comprising a pair of substantially parallel connection members, two fixing nails held between said two parallel connection members, each connection member comprising two parts, at least one resilient element means for detachably interconnecting said two parts of each connection member, a pair of supports each equipped with a respective pair of crosswise arranged fixing wires, wherein at the corresponding parts of both connection members there is adjustably and detachably secured one of the fixing nails and one of the supports which is disposed in a plane substantially perpendicular to a plane taken through the fixing nails.

2. The fixator for diaphyses fractures as defined in claim 1, wherein one of said two parts is constructed as a rod and the other of said parts as a sleeve member pushed over such rod.

3. The fixator for diaphyses, fractures as defined in claim "1, further including means for adjusting the spring force of the resilient element means.

4. The fixator for diaphyses fractures as defined in claim 1, further including means for arranging the attachment ends of the fixing wires adjustably at the associated support.

5. The fixator for diaphyses fractures as defined in claim 1, wherein each support possesses a substantially half moon-shaped configuration. 

1. A fixator for diaphyses fractures, comprising a pair of substantially parallel connection members, two fixing nails held between said two parallel connection members, each connection member comprising two parts, at least one resilient element means for detachably interconnecting said two parts of each connection member, a pair of supports each equipped with a respective pair of crosswise arranged fixing wires, wherein at the corresponding parts of both connection members there is adjustably and detachably secured one of the fixing nails and one of the supports which is disposed in a plane substantially perpendicular to a plane taken through the fixing nails.
 2. The fixator for diaphyses fractures as defined in claim 1, wherein one of said two parts is constructed as a rod and the other of said parts as a sleeve member pushed over such rod.
 3. The fixator for diaphyses fractures as defined in claim 1, further including means for adjusting the spring force of the resilient element means.
 4. The fixator for diaphyses fractures as defined in claim 1, further including means for arranging the attachment ends of the fixing wires adjustably at the associated support.
 5. The fixator for diaphyses fractures as defined in claim 1, wherein each support possesses a substantially half moon-shaped configuration. 